Devices proposed in the prior art for detecting the level within a bin of a pulverulent fluent material have used mechanical linkages and movable parts within the bin to operate an electrical switch that in turn operates a filling mechanism or a warning device such as an alarm or light. Such devices offered as optional equipment for bins require the manufacture and assembling of a number of parts which must then be fitted into the bin level detector. This adds expense to the overall production of the bin. Such devices are at least partially located within the bin and operate in response to the pressure of the particular pulverulent, fluent material to be contained within the bin. Gravel and feed grain products are examples of such materials. The flow of such materials generates an abundance of dust and particulate material within the atmosphere of the bin. This dust and particulate material frequently foul or damage the mechanical linkages and movable parts present in previous devices preventing proper operation. Damage of this sort is often expensive to repair and can lead to secondary damage to filling mechanisms that are not shut off when the bin is full. A recurring example of such damage arises when a bin is full and a damaged switch does not shut off an electrical motor operating a feeding auger. The auger continues to push grain, feed, or some other material against a full bin until the motor burns up, blows fuses or damages the auger.